Transmission and control therefor



lifl- A.

June 14, 1960 J. M. SIMPSON ETAL 2,940,336

TRANSMISSION AND CONTROL THEREFOR Original Filed Jan. 9, 1942 5Sheets-Sheet 1 1; Mer er-5'" kfo firzjfjz'ngyson 15 2070222 E car/20 9MJune 14, 1960 J. M. SIMPSON ErAL 2,940,336

TRANSMISSION AND CONTROL THEREFOR Original Filed Jan. 9, 1942 5Sheets-Sheet 2 June 14, 1960 J. M. SIMPSON ETAL 2,940,336

musmssron AND CONTROL THEREFOR Original Filed Jan. 9, 1942 5Sheets-Sheet 3 772 05072, firoicifl Ca r72. ayuw June 14,1960 J. M.SIMPSON ETAL 2,940,336

TRANSMISSION AND CONTROL THEREFOR Original Filed Jan. 9. 1942 5Sheets-Sheet 4 J1me 1960 J. M. SlMPSON HAL 3 9 wmnsmssxou AND CONTROLTHEREFOR Original Filed Jan. 9, 1942 5 Sheets-Sheet 5 IPA-VERSE 2/7 .1.Asp

a 2/5 2/5 mgr 6 l 1 FOIWAIP I J29 I /525 J39 United States Patent OTRANSMISSION AND CONTROL THEREFOR 'John M. Simpson, deceased, late ofAsheville, N.C., by

First National Bank and Trust Company, administrator, Asheville, N.C.,and Harold E. Carnagua, Fort Wayne, Ind., assiguors to Borg-WarnerCorporation, Chicago, 111., a corporation of Illinois Continuation ofapplication Ser. No. 426,122, Jan. 9, 1942. This application Jan. 11,1957, Ser. No. 633,770

60 Claims. (Cl. 74-'645) This invention relates to automatictransmissions and particularly to that type of transmission whichemploys a hydraulic torque converter combined with gearing.

This application is a continuation of the application of John M. Simpsonet al., filed January 9, 1942, S.N. 426,122, now abandoned forTransmission and Control Therefor.

The principal object of this invention is to provide an improvedautomatic transmission of the hydrodynamic type combined with gearingwhich will be simpler and more eiiicient than those heretofore proposed.

Another object of this invention is to provide an automatic transmissionof the hydrodynamic type combined with gearing wherein manually operatedpositive types of controls are used for low and reverse drives forgreatest efliciency, hydraulically operate/i controls are used forintermediate and direct drives, and electrical means are used to controlthe hydraulic controls for greatest simplicity.

Another object of this invention is to provide a transmission of thehydrodynamic type combined with gearing wherein a common releasablereaction is used for both the gearing and hydrodynamic device, withmeans for releasing the hydrodynamic device from the reactionindependently of the gearing.

A more specific object of this invention is to provide a lockupmechanism for a hydrodynamic torque con verter which is extremely lightso as to reduce to a minimum the rotational inertia of the fly wheel andassociated rotating parts.

Yet another specific object of this invention is to provide an automatictransmission of the hydrodynamic type combined with gearing wherein allrotatable parts are made as light as possible to facilitate fastshifting and to promote faster acceleration of the engine.

These and other objects and features of this invention will becomeapparent from the following specification when taken together with theaccompanying drawings in which:

Fig. 1 is a schematic view of the transmission showing the mechanicalfeatures, the hydraulic circuits and the electrical controls for thehydraulic circuits;

Fig. 2 is a side elevation in section of the transmission showing atypical arrangement of the parts;

Fig. 3 is a section taken through the transmission along line 33 of Fig.2;

Fig. 4 is a second section taken through the transmission along line 44of Fig. 2;

Fig. 5 is a fragmentary section somewhat enlarged taken approximatelyalong line 5-5 of Fig. 2;

Fig. 6 is a schematic diagram of the external controls for thetransmission; and

Fig. 7 is a wiring diagram showing the electrical controls for thetransmission.

In general, the preferred embodiment of the transmission is comprised ofa hydrodynamic torque converter of the three-element type comprising apump, a turbine and a stator combined with a single planetary gear setin its? such a manner as to obtain two torque-converting driving rangesand a purely mechanical direct drive. Reverse is obtained through theconverter rather than by means of the gearing, the functions of thestator and turbine elements being interchanged to secure this result.The pump element of the torque converter is permanently secured to thefly wheel of the engine and a definite neutral is obtained by releasingall clutches and brakes so that there is no direct connection betweenthe driving and driven elements, nor is there any point against whichthe driving element can react. A positively interengageable device,manually operated, is used to provide a reaction point for forward driveon starting out, and this device remains engaged regardless of the speedat which the vehicle is moving or the engine is rotating.

Another positively interengageable manually controlled device is usedfor securing a reverse drive and this device likewise remains engaged aslong as the transmission is conditioned for reverse. A third positivelyinterengageable device, manually controlled, is provided when it isdesired to start the engine by pushing the vehicle. A clutch is used tolock up the hydrodynamic torque converter, and another clutch is used tolock up the planetary gear set. The lock-up clutch, as well as the brakemeans and direct-drive clutch, are all made of stampings'or lightweightcastings to reduce rotational inertia to a minimum. The transmission isoperated in such a manner that it will start with both the torqueconverter and a planetary gearing multiplying torque and at somepredetermined speed, as for example, twelve miles per hour, both thetorque converter and the gearing will be simultaneously conditioned tolock up. The locking up may be delayed by means of a vacuum-operatedswitch which remains open until the accelerator pedal is released toincrease the vacuum. If the accelerator pedal is maintained continuouslydepressed above a speed of, say, thirtymiles per hour, the torqueconverter will automatically lock up despite the fact that thevacuum-operated switch is 'still open, but the gearing will stillmultiply torque until the accelerator pedal is released. Between twelveand thirty miles per hour a simultaneous downshift may be effected inboth the torque converter and the gearing. Above thirty miles per hour adownshift is possible only in the gearing since at speeds above thirtymiles per hour the torque converter would have no torque multiplyingcharacteristics and hence would not contribute anything to theacceleration of the vehicle.

Referring now to the drawings for a detailed description of theinvention and particularly to Fig. l, the transmission is comprised of adrive shaft 10, which may be connected to a prime mover such as internalcombustion engine 11, a hydraulic torque converter 12, a planetary gearset 13 and a driven shaft 14. The torque converter 12- is connected togearing 13 by means of a shaft 15 and also by means of a concentrichollow shaft 16. A lock-up clutch 17 is used to obtain a mechanicaldrive through the front end of the transmission around converter 12, amultiplate friction clutch 13 is used to lock during forward drivefunctions as a one-way brake and during reverse drive functions as aclutch. Within housing 22 is an annular cylinder 27 in which isslidably, but not rotatably, received an annular .piston 28 having apressure transmitting member 29 secured thereto. Housing 22 is alsoprovided with an inwardly extending flange 30 from pressure transmittingmember 29. Within the space between flange 30 and member 29 is a friction plate 31 which is secured to rotate with shaft 15.

It-will be observed that when piston 28 is moved to the right (Fig. 1).so as to clamp friction plate 31 against flange 30, drive. shaft will bedirectly and mechaniv cally connected to shaft 15, thereby locking uptorque therewith and a plurality of double planet pinions 36 and 37.mountedon carrier 35. Said planet pinionsrare so arranged that a pinion36 will mesh with ring gear 32 and also with planet pinion 37, and saidplanet pinion 37 will mesh' with sun gear 34. V

Brake 19 is connected to hollow shaft 16 through a of driven shaft 14reached, governor 58 will condition electrical circuit 57 and solenoid56 to move valve 48 roller-and-cam device 38, and brake is connecteddirectly to hollow shaft 16. Brake 21, is connected to carrier -35.Brake 19 is comprised of a toothed ratchet wheel 39 and a radiallyslidable, rotationally fixedpawl 40.- Brake 20 is comprised of a ratchetwheel 41 and a radially slidable, rotationally fixed pawl 42 (Fig. 5Brake 21 is comprised of a ratchet wheel 43 and a radially slidable,rotationally fixed pawl 44.

Clutch 18 is controlled by means of a piston 45 received-in an annularcylinder 46 formed in drum 33. Said piston 45 is operated by fluidpressure introduced into cylinder 46 through a conduit 47 in which isinterposed a selector valve 48. Said valve 48 is also interlshaft16, 51in shaft 15 and 52 in fly-wheel housing 22 .toannular cylinder 27 infly-wheel housing 22. The hydraulic pressure is derived from a pump 53which is driven'through a shaft 54 from suitable gearing 55 connecteddirectly to housing 22.

, Selector valve 48 is controlled by a two-stage solenoid i 56 which inturn is controlled by a suitable electrical circuit 57 from a governor58 driven from driven shaft 14.

Neutral is obtained by releasing all clutches and brakes.

V This means that clutch 18 is released so as to break the so that anypower transmitted to housing 22 is passed on to-shaft 15 through torqueconverter 12 only.

To start the vehicle from a dead stop, brake '19 is applied and allother clutches and brakes are released. This provides a reaction for sungear '34 through rollerand-cam device 38'-which is designed to preventreverse rotation of the sun gear. Roller-and-cam device26 is :arrangedto prevent reverse rotation of stator 25 relative to hollow shaft 16 andhence, when brake 19 is applied, sun gear 34 and stator 25 are both heldagainst reverse rotation. Torque impressed on drive shaft 10, therefore,is multiplied in hydraulic torque converter, 12 and transmitted to shaft15, from which it passes through carrier 35, ring gear 32 and drum 33 todriven shaft 14,- planetary gear set 13 likewise multiplying the torqueas it is received from shaft 15. It will be noted thatsince pump 53is'driven directly from housing 22, full hydraulic pressure isavailablewhenever shaft 10 is-rotating.- No hydraulic pressure is required by thetransmission for starting the car except such as is necessary in housing22 for the operation of torque converter- 12. The proper distribution offluid under pressure to housing 22 is effected by means of a conduit 59con- 1 nected to pump 53, a pressure-regulating valve 60 which providesfluid under relatively high pressure for the operating of the variousclutches and brakes, and a conduit 61 leading to housing 22, thepressure in conduit 61 being maintained at a lower value by a secondpressure-regulating valve 62. When a predetermined speed of rotationdriven. shaft 14.

in a manner to admit fluid under pressure to both lock- .up clutch 17and clutch 18. The actual operation of hereinaften so that if continuedtorque -is required above a, predetermined speed, the transmission willrespond and provide the torque." Above ahigher predetermined speed,however, regardless of torque requirements, clutch 17 is engaged to'lockup torque converter 12, but clutch 18 will still remain disengaged untilthere is a let-up in the torque demand. When the latter conditionexists, clutch 18 will likewise be engaged so that there'will be adirect mechanical drive provided between drive shaft '10 and drivenshaft '14through clutch 1-17, intermediate shaft 15 and clutch '18.During all this time, brake 19 is applied and remains so. Stator25,.however, will .rotate forwardly with the pump and turbine elements..23. and 24 respectively, just as soon as the fluid withinthe torqueconverter begins to impinge upon the backs of :thevanes of the stator.The presence-of the roller-and-cam device 38' makes this possible.Similarly when clutch 18 is engaged so as to cause ring gear 32, carrier35 and sun gear 34 to rotate as a unit, gsuch rotation will be madepossible despite the continued engagement of brake 19becauseroller-and-cam device'38 is designed to release the sun gear 34when the latter tends to rotate in a forward direction. I

Reverse is obtained by releasing brake 19 and engaging brake 21. Thisarrests the rotation of carrier 35, shaft 15 and turbine element 24 andreleases sun gear 34, as well as stator element 25, for backwardrotation. Under 'these conditions, with pump element 23 rotating in aforward direction and the turbine element 24 sta tionary, stator element25 will rotate in a reverse direction, thereby rotating sun gear 34reversely with it. This reverse rotation is transmitted throughplanetary gears '36 and37 to ring gear 32 and then through drum 33 toJust prior tothe engagement of reverse brake 2 1, electrical circuit 57is so conditioned that no fluid pressure can be admitted to clutches I17 and 18 so as to tend to drive two frictioually engaged elements inopposite directions simultaneously. The manner in which circuit 57 is soconditioned will be describ'edhereinafter.

In order to start the engine bypushing the vehicle,

. brake 20 is applied and all other brakes andclutches are released.Said brake 20 provides a reaction for sun gear 34 which would otherwisebe absent because of theteleasing effect of roller-and-cam device 38.With sun gear 34 held stationary and driven shaft 14 rotated, a drive isimpressed upon carrier 35 which in'turn is transmitted to shaft .15 andthence because of a special feature incorporated in clutch 17 wherebysaid clutch is rendered operative whenever fluid pressure is' absent inhousing 22, said drive will be transmitted to housing 22 to rotate shaft10 of the engine 11. Brake 20 is so designed that it will automaticallyrelease when engine 11 begins to drive.

7 I Having thus described the principal features of the transmission andthe general operation thereof,.a detailed description 'of the mechanismsinvolved in the various features willnow be described.

Fly wheel housing 7 Fly wheellhousing 22 (Fig. 2) is comprised of aplurality of castings 65, 66 and 67, casting 65 being bolted directly toa flange 68 on shaft 10, and casting 66 being secured to casting 65 andto casting 67 by means of machine screws 69 and bolts 70 respectively.Casting 67 functions as a lshroud'for torque converter 12 and isprovided with a sleeve 71 which extends rearwardly from as to permitrelative axial movement between housing 22 and drive gear 55, and alsoto provide an adjustment between these two elements if there should be aslight misalignment between them. The fluid within housing 22 isprevented from escaping by means of one or more piston rings 75 and alsoby means of a seal 76, the former being inserted between the casting 67and shaft 74 and the latter being inserted between casting 67 and aportion of the casing 77 which surrounds and supports the transmissionas a whole.

Annular piston 28 is held against rotation relative to casting 65 bymeans of a plurality of pins 78 which are fixed to casting 65 and passthrough suitable notches in the piston. A plurality of springs 79,retained in casting '65 by means of pins 80, constantly urge piston 23to the right (Fig. 2) to engage clutch 17. It is contemplated thatsufficient pressure will be developed by springs 79 to enable clutch 17to drive the engine for a push start.

Ratio clutch In order to facilitate distinguishing between the lock-upclutch for the torque converter and the lock-up clutch for the planetaryset, the first-mentioned clutch will be termed hereinafter the directdrive clutc and the latter will be termed the ratio clutch.

The ratio clutch (Fig. 2) is comprised of a light casting 81 splined toshaft 15 and having external splines 82 which engage and drive aplurality of driving clutch plates 83. Said plates 83 are provided withfriction facings 84 which engage driven discs 35 locked in an annularcasting 35 secured to drum '33. Casting 86 serves as a reaction memberfor clutch is. Said drurn 33 may be fabricated from either a stamping ora very light casting and is riveted or otherwise secured as at 87 to aflange $8 on driven shaft 14. Piston 45 is secured against rotationrelative to drum 33 by means of a plurality of pins 89 which passthrough the piston, discs 85 and casting 86.

The positive brakes Brakes 19, 2t and 21 are of the same general type inthat each is comprised of a rotatable ratchet wheel and a non rotatableradially slidable pawl. The general construction of these brakes isillustrated in Fig. 5. As shown in this figure wherein brake 21 isillustrated, it will be seen that ratchet wheel 43 is provided withrelatively sharp teeth 94 each of which is provided with a load-holdingface 91 and a camrning face 92. Similarly, the cooperating pawl 44 isprovided with a relatively sharp tooth 93 having a load holding face 234and an ejecting face 95. In view of the sharpness of the teeth on boththe pawl and wheel, it becomes imperative to prevent a partialengagement of the teeth such that the tips of the teeth will be broken.To this end a blocker mechanism 96 is provided. Said blocker mechanism96 is comprised of a ring which is oscillatable relative to ratchetwheel 43 through a slight angle. The blocker 96 is provided withsubstantially square-shaped teeth 97, the ends of which coincide withthe ends of teeth Ed on the ratchet wheel. Said ratchet wheel isprovided with a pin 98' which rides in a notch 9? in blocker mechanism96 so as to limit the oscillatory movement of said blocker relative tothe ratchet wheel. A spring 166 is tensioned between an ear 131 formedin wheel 43 and an ear Hi2 formed in blocker 95, said spring 1%maintaining blocker 96 in such position relative to ratchet wheel 43that teeth 97 prevent radial inward movement of the pawl 44 intoengagement with the wheel except when such engagement begins asubstantial distance behind the tip of the tooth. In this manner, pawl44 will have sufiicient time to move radially inwardly to prevent such apartial engagement as would harm either the pawl or the wheel.

Ratchet wheel 39 is provided with a similar blocker 103 (Fig. 2), thedetails of which are disclosed in the .copending application of John M.Simpson, Serial No.

described in detail herein.

It is contemplated that brake 20 will be engaged while ratchet wheel 41is stationary and hence, no blocking mechanism is necessary for brake20.

Auxiliary braking mechanism for the positive brakes It is a well-knownfact that where a hydraulic power transmitting device, such as the oneillustrated, is permanently connected to the drive shaft of an internalcombustion engine, the hydraulic device will transmit a certain amountof drag torque when the engine is idling. This drag torque is, ofcourse, impressed upon shaft 15 in the transmission shown and is alsoimpressed upon carrier 35 of planetary gear set 13 and to the gears associated therewith, including ring gear 32 and sun gear 34. When ring gear32 is permanently connected to the driven wheels of the vehicle and is,therefore, under load, said ring gear will act as a reaction element forthe planetary gear set while drag torque is impressed upon carrier 35,and as a result, sun gear 34 is rotated just prior to the engagement ofeither the forward brake 19 or the reverse brake 21. It is also awell-known fact that a positiveacting control device, such as a ratchetand pawl or other toothed interengageable elements, cannot be engagedreadily while torque is impressed upon one or the other of the elements.To avoid this condition in the present transmission, therefore, anauxiliary brake is provided which halts the rotation of the movableelements of brakes 19, 2t? and 21 just prior to the engagement of eitherbrake 19 or 21. The auxiliary brake is a friction brake and hence, maybe engaged under torque. This brake is shown generally at 164 (Fig. 2)and is comprised of a pressure membe 195 operated by an annular piston1% located in a cylinder 1%7 in casing 77. Cooperating with pressuremember 105 is a friction facing 16% secured to ratchet wheel 39. Thepressure is transmitted through ratchet wheel 39 to a friction facing109 on ratchet wheel 41 and then through a friction facing 110 on theopposite side of ratchet wheel 41 to a fixed abutment member 111, saidabutment member 111 being secured to casing 77 by means of one or morebolts 112. A pin 113 passing through abutment member 111 and throughpiston 1G6 prevents the latter from rotating relative to casing 77 Whenpiston 11% is urged to the right (Fig. 2), pressure member 195 engagesfriction facing 19% and arrests the rotation of ratchet wheel 39. Itlikewise arrests the rotatiton of ratchet wheel 41 by reason of the factthat the latter is pressed against abutment member 111. With sun gear 34held against rotation in this manner and ring gear 32 held againstrotation because of the load impressed thereon, carrier 35 will becompelled to stop rotating and accordingly, ratchet wheel '43, which issecured to carrier 35, will likewise be stationary.

Thus, the application of brake 194 arrests the rotation of all of therotatable elements of the positive brakes 19, 20 and 21.

The stopping of the rotatable elements of the positive brakes does notprovide a complete solution to the problem, however, inasmuch as theratchet wheels may come to rest with the blockers interposed in the pathof movement of the pawls. It becomes necessary, therefore, to releaseauxiliary brake 104 just prior to the engagement of a ratchet wheel witha pawl so that the drag torque may be utilized to rotate the teethsufificiently to move the blockers out of the way. The manner in whichthis is done will now be described.

Combination valve and pawl It will be observed from Figs. 1 and 2 thateach pawl is provided with a relatively long stem, which stem functionsas a valve. Specifically, pawl 49 is provided with a stem 114 which iscut away at 115 to provide a passageway for fluid under pressure. Saidpassageway 115 communicates with a conduit 116 in casing 77 whichcomratchet wheels '39, 41 and '43 mummies directlywithicylinder. 107.Similarly, pawl 44 is provided with a stern 117 in whicharetwopassageways 11-8, and'119; A passageway 120. is providedfor-interconnecting passageways 118 and 115; andalso for con:

necting passageway 115 'withpassageway 119 "and then to'a return conduit121 which connects with sump 64. Fluid underpressure is admitted topassageway 1 18 through'a conduit 122 from pump 53 by way of valve 63.shown in Figs. 1 and 2, pawls 40 and 44 are in a neutral position andwhen so positioned, fluid under pressure will be admitted throughpassageways 118, 120, 115 and 116 into cylinder 197 to stop the rotationof the It is contemplated that when either pawl 40 or pawl 44 is movedinto engagement with its respective ratchet wheel the other pawl will beretracted to -a position farther removedfrom its ratchet wheel. To thisend each stem L14 and-117 is made with a lateral slot 123 and 124respectively, in each of which is mounted a roller 125 and 126respectively, secured to a pivoted lever 12% which may be rocked by ashaft 13% mounted in casing 77; The various passageways are so arrangedthat when the pawls are in a neutral position, piston 106 will be biasedto engaged position, but when either pawl is moved towards its'engagedposition, the-fluid pressure will automatically be dumped by connectingthe cylinder to dump conduit 121. During such time as the cylinder isconnected to the dump conduit, the pressure conduit 122 is blocked offby the body of pawl 44. 'This results in a release of brake 106 justprior to the engagement of a ratchet wheel with a pawl, and since thedrag torque of the torque converter 12 is constantly impressed upon theratchet wheels, the

latter-will, begin to rotate and the blocker, if it was originallylocated in the path of movement of a pawl, will automatically be rotatedout of the way. It will be observed that the shift from forward toreverse requires that the pawls 40 and 44 be positioned in neutral atsome intermediate stage of the movement from forward to reverseposition, and accordingly, brake 166 will 'always'be applied and thenreleased in shifting between forward to reverse, as, for example, inparking a car. This will automatically arrest the rotation of eachratchet wheel to remove drag torque and then permit the wheels to'rotatereleased-to move the pawl into complete engagement with its ratchetwheel when the pawl .is' free.

, To avoid jarring a pawl out of engagement afterit has once beenengaged, plunger 134 is provided with anotch 141-in which is adapted tobe received a latch 142 which is constantly biased by a spring 143toward plunger 134. While in neutral, and through a short are on eitherside of neutral position, latch 142 is held'in a withdrawn position bya'cone 144 secured to the end of the latch 142- Push start control Asdescribed above. in connection with the general operation of atransmission, no hydraulic pressure is available when drive shaft 10 isnot rotating and accord under the influence of drag torque to avoid abutt-ended 7 7 condition between a pawl and its ratchet wheel.

Manilal control for pawl As shown in detail in Fig. 5, rock shaft 130 issecured at its left-hand end (Fig. 5) to an upright lever 131 V which isprovided with a parallel-sided 8101132 in the free end thereof. Ridingin slot 132 is pin 133 which is secured to a plunger 134 riding in adeep socket 135 formed in a lever 136. Said lever 136 is provided withan elongated parallel-sided slot 137 in which pin 133 likewiseis adaptedto ride. Lever 136 is pinned to a rock shaft 138 to the free end ofwhich (lefthand end'in Fig. 5) is secured an external control lever 139.A spring 140 normally biases plunger 134 to its limiting positionin adownward direction as determined by pin 133 striking the lower end ofslot 137. It is contemplated that by oscillating lever 139 and itsassociated rock shaft 138, the oscillatory movement will be transmittedthrough 'lever 136, plunger 134, pin 133 and lever 131 to rock shaft130. Since slots 137 and 132 are adapted to be crossed in any one of anumber of different positions, the movement of the latter does notnecessarily mean that the movement of the former Will follow. Thepurpose of this arrangement is to permit lever 139 to be moved to theend of its travel in spite of the .fact that aipawl may beblocked andits associated levers and pins, up to and including lever 131, may notbe able to follow the movement of lever 139. Under such blockedconditions, however, pin133 is forced upward, in its slot to compressingly, it is not possible by the ordinary means provided in thetransmission to secure a driving connection from driven shaft 14 todrive shaft 10 such as would enable the operator to start the engine bypushing thevehicle. Since no pressure is available, there is no forcecreated within housing 22 tending to move piston 28 to the left (Figs. 1and 2) against the action of springs 79 to release c'lutch 17 andaccordingly, said clutch is engaged and remains engaged under the actionof springs 79 whenever drive shaft 10 ceases to rotate. This provides adirect connection between intermediate shaft 15 and drive shaft 10, andit remains, therefore, merely to provide a connection between said shaft15 and driven shaft 14 in order to elfect the starting of the engine bypushing the vehicle. This connection is shown in Fig. 5 andqcomprisesthe pawl 42. previously mentioned and suitable external controls for thepawl.

Pawl 42 is radially slidable in an opening 200 in casing 77 and isprovided with a stem 201 of lesser diameter than the diameter of thepawl. A pawl operator 148 is likewise received in opening 200 and isslidable radially therein. Said operator 148 has an opening 149 thereinfor receiving the end of stem 201. A pin 150 passing throughstem 201 andriding in a slot 151 provides a lostmotion connection between o erator14S and-stem 201 such that operator 143 may move radially inwardlywithout requiring that stem201- do likewise. A spring 152 is normallycompressed between operator 148 and pawl 42 so that it tends to separatethe two and take up the lost-motion connection. Should'operator 148bemoved radially inwardly while pawl 42 is butt-ended with respect to itscorresponding ratchet wheel 41, the radial inward movement of operator148 will merely compress spring 152 and store up energy which islater'utilized when the butt-ended condition ceases to exist, to urgepawl 42 into full engagement with its ratchet wheel.

Operator 148 is formed with a transverse slot 153 in which is mounted aroller 154 rotatably secured to the end of a crank 155 of a smalloscillatable crank shaft 156. Said crank shaft 156 is mounted in a lug157 in casing 77; A crank 158 mounted on the free end of crank shaft 156is connected to a rod 159 which in turn is connected to a second crank160 mounted in a boss 161 in casing 77. vSaid crank 16!) extends upwardfrom casing 77 in the form of a lever 162 the end of which may beconnected by means of a Bowden wire 163 or the like to a suitablecontrol (not shown) at the dash of the vehicle. Thus, by pushing orpulling Bowden wire 163, lever 162 will be oscillated through a smallare which in turn will .move rod 159 vertically, thereby rotating crankshaft 156 and reciprocating operator 148 in opening 200. The

140 and thereby storeup energywhich is later I reciprocation of operator148 is transmitted to pawl 42 through pin-and-slot connection 150, 151and spring 152 to engage or disengage pawl 42 with its ratchet wheel 41.When pawl 42 is engaged with its ratchet wheel, a positive reaction isprovided for sun gear 34, and the rotation of driven shaft 14 whichresults from pushing the vehicle is then transmitted through theplanetary gear train to shaft 15 which, as We have already seen, isdirectly connected to drive shaft 19 through clutch 17. Just as soon asthe engine begins to rotate under its own power, ratchet wheel 41 willrotate in a manner to eject pawl 42 therefrom, assuming, of course, thatthe transmission is in neutral so as to permit the engine to rotatefreely. The ratcheting sound produced by the ejection of pawl 42 fromratchet wheel 41 informs the operator that the reaction provided by pawl42 is no longer necessary and he may then operate Bowden wire 163 in amanner to release pawl 42 from its ratchet wheel 41.

The hydraulic circuits It will be remembered that when drive shaft 18 isrotating, pump drive gear 55 is likewise rotating and accordingly, pump53 will be driven to deliver fluid under pressure to conduit 59. Saidconduit 59 is a branch of a principal conduit 164 which has two otherbranches 165 and 166. Valve 63 is interposed in conduit 164 and isprovided with radial portings 167, 168 and 169' which are so arrangedthat when the valve is in the position shown in Fig. l, conduit 164communicates with conduit 122 leading to the valve attached to the pawl,and when valve 63 is rotated in a clockwise direction to a position 45degrees removed from that shown, conduit 122 will be blocked off andconduit 164 will communicate directly with a dump conduit 178 leading tosump 64. It is contemplated that valve 63 will be moved in a counterclockwise direction to an intermediate position 45 from that shown whenthe transmission is conditioned for neutral so that passageway 122 isconnected to dump conduit 17b to insure the release of all of the brakesand that porting 168 will not be aligned with dump conduit 178 so thatpressure will be available in the remainder of the system. When thetransmission is in neutral, pump 53 supplies fluid under pressure toconduit 59, 164, 165 and 166. The pressure in these conduits will beregulated by pressure regulating valve 69 to that required for theoperation of the various clutches and brakes. This pressure, of course,may be varied to suit the particular requirements of the transmissionand may be as high as sixty pounds per square inch if necessary. It hasbeen found, however, that for the operation of the torque converter, alesser pressure may be sufllcient and accordingly, a second pressureregulating valve 62 is used which operates on the fluid as it leaves thefirst pressure regulating valve 69 and regulates the pressure in conduit61 and the torque converter chamber in communication therewith toapproximately thirty pounds per square inch. All fluid in excess of thatrequired to maintain the desired pressure in line 61 is then returned tosump 64 by means of a return conduit 171.

It will be remembered that springs 79 normally bias opposed by thehydraulic pressure, and it is contemplated that the latter shall exceedthe former so that the clutch will be released just as soon assufficient pressure is-builtup within the housing. When in neutral,therefore, and with the engine running, clutch 17 is disengaged and willnot be reengagecl until fluid at a higher pressure is admitted on thespring side of piston 28. When the transmission is conditioned forforward drive,v a control: lever at the steering column (hereinafter tobe described). is provided having two directions of movement, the firstof which rotates valve 63 in a manner to admit fluid under pressure toline 122 and the second ofwhich oper- 10 ates external lever 139 of the"pawl control system to move one or the other of thep'awls into engagmentwith its'ratchet wheel. The hydraulically operated brake will" then becontrolled in accordance with the movement of the pawls and theirassociated valves as described hereabove.

Clutch control valve 48 is a two-part valve, the first part comprisingland's172' and 173' controlling lockup clutch 17 and the second partcomprising lands 174 and 175 controlling ratio clutch 18. A common land176 separates the two parts. The porting of the valve block 177 is soarranged that in one position of the valve, fluid will be admitted toclutch 17' butnot to clutch 18, and in a second position fluid will beadmitted to both clutches. When fluid under pressure is not being ad'-mitted' to' either clutch, the porting is such that the fluid will bedrained into dump passageway I71.

Valve 48 is normally urged to a: dumping position by a tension spring178 and is urgedin the opposite direction by a two-stage solenoid 56,said solenoid being comprised of two sets of windings independentlycontrolled,v each set being eflFective to move the valve through a givenThe solenoid is electrically controlled from. governor 58 and controlcircuit 57 as will now be dedistance.

tailed.

Electrical circuits The electical circuit as shown in Fig. 7 and intheembodiment selected for illustrative purposes is cormprised of abattery 179, or other suitable source of electromotive force and twomain branches 180 and 181. Im branch 188 is a relay 182 having a pair ofcontacts 183 which are adapted to connect the battery to a starter :184.Relay 182 is controlled by a starter switch 185 of the usual variety anda special control switch 186 in series with the starter switch. Switch186 is controlled by the hand lever (hereinafter to be described) insuch a manner that the starter may not be operated unless the lever isin a neutral position.

In branch 181 is a main control switch 187 which is likewise operatedbythe hand. control lever so as to renderv the entire second. branchinoperative when the transmission is conditioned for reverse, since inreverse the drive and driven members of the clutches 17 and 18 areintended to rotate in opposite directions relativeto one another, and itis imperative, therefore, that these clutches shall not'b'e engaged whenthe transmission is in reverse. In series with switch 187 is a downshiftorkickdown switch 188 having two pairs of contacts 189' and 190 locatedin parallel circuits leading from switch 187. The switch is preferablyoperated by the accelerator pedal 241 although it may also beoperatedindependently. In series with each pair of contacts 189 and 190 arespeed controlled switches 1-91 and 192 respectively, both of which maybe operated by governor 58 to close at approximately twelve miles perhour. Another switch 193 having pairs of contacts 194 and 195 in series,respectively, with governor switches 191 and 192 is used to delaytheoperation ofthe solenoid in accordance with the torque requirements ofthe operator. To this endswitch 193 is operated-by a-pressuredifierential device 196 havingv a diaphragm 197 connected to to theswitch 193, a spring 198 normally tending to disengage contacts 194 and195, and a vacuum line 199 connected to the engine manifold (not shown).

Contacts 194 are. connected to a ratio relay- 202 and contacts 195 areconnected to a lockup relay 203. Ratio relay 202- is provided with a.pair of contacts 204- which connect the battery to operating coil 205and holding coil 206 of the ratio portion of solenoid 56. Lockup relay203 is provided with a pairof contacts 207 which pair of contacts f -210and 211; respectively;-which are.

normally closed so as to completethe circuit through Qpicrating coils205- and 208 respectively, ,but which break? the circuitthroughfsaidcoils upon movement of there spective umaturcs, thereby, reducing thedrain on the battery. Each armature, meanwhile, is maintained in itsoperative position by its holding coil 206 or 209. 'In this respect, thearmatures, Operating coils, holding coils and circuit.breakingswitches-are similar to those ,used on commercial overdrives; I1

or the like, is used to connect the battery directly to lockup relay 203above a predetermined speed of the vehicle.

This renders'lockup relay 203, independent of vacuum control switch 193at-the governed speed of switch 212 so that regardless of torque demandthe torque con verter will be locked up. a

Theoperation of the circuit is as follows: Assuming that the controllever is in neutral and switch 186, therefore, closed, the engine isstarteclby closing,

starter switch 185 and the operator thenconditions the transmission forforward operation and in so doing closes siwitch187 and opens switch 186. *Downshift switch 188 is normally held in a;p osition to completethecircuit across contacts 189 and 190. and governor switches 191 and 192are open. The circuit to relays 202 and 203 are, therefore, broken andvalve 48 is in adumping position. When the operator depresses theaccelerator .pedal 241 to start the vehicle 'moving, there isinsuflicient vacuum to overcome spring 198 of pressure differentialdeyice196 and the circuit across contacts 194 and 195 controlled byswitch 193 is broken. This condition obi 10' P A' speed responsiveswitch 212, such as a wind switch I ratio clutchesFwill be released andtorquemultiplication will be-provide'd. through the converter as well asthrough the gearing. T I i f l Manual controls' Thefmanual controls areshown in Fig.6 and are operatedby'rne'ans of a single lever 215,preferably located beneath the steering wheel, which is adapted to bemoved from a depressed central position corresponding to a neutralposition to a raised and then counterclockwise rotated positioncorresponding to reversenand a raised clockwise rotated positioncorresponding to forward position. c j V Said lever 215 is pivoted at216 to an axially fixed rotatable rod 217 and is also pivotallyconnected to a bracket 218 which surrounds rod 217 and is rotatablerelative thereto. Said bracket 218 is axiallymovablej relative to rod217 in response to vertical movement of lever-215. The pivotal supportfor bracket 218 is comprised ofa relatively long hollow tube 219 whichmay be supported from a fixed bracket'220." Said bracket 220 is 'formedwith a pair of spaced lugs 221 and 222 between which is 'pivotallymounted a lever 223. Lever 223 is provided with a depending extension-224 in which is located a notch 225. Opposite extension 224 is a fixedbracket 226 having anopposed notch'227 therein. Tube 219 is providedwith a laterally extending lug'228 which is adapted to ride in one orthe other of the notches 225 and 227. Tube'219 terminates in a ball 229to which is pivotally mounted a lever 230 passing through and fulcrumedin an aperture 231 in bracket 226. Aligned with the pivotal connectionbetween lever 230 and ball 229 is switch 186 which, as we have seen,controls the starter circuit. Two bell cranks 232 and 233 are operatedby lever 230, bell crank 2 33 being connected by a rod 234 to valve 63and bell crank 232 being connected by rod 235 to the valve 236 of thecarburetor of the engine whichcontrols the idling speed thereof. 7 V

Lever 223 is connected-by a'rod 237 toexternal control 139 for pawls 40and 44. Lever 223 also operates switch 187 which is used to renderoperative or inoperaswitch 193 will complete bothicircuits' and relays202 I and 203 will operate to connect thev battery to; both the locknpand ratio solenoidsq Both clutches controlled by these solenoids willthen engage and'the transmission will be in direct drive. A To 'avloidaconstanten'gagement and disenega'gernent of the clutches "duringoperation above agoverned speediof switches 191 and 192 such aswouldresult'frorn the sucessive nraking. and, breaking of the,

circuit throughlswitch 193 by reason of the accelerator pedal beingrepeatedly raised and depressed, resistances 213 and-214 are connectedacross contacts 194 and 195 respectively, said resistances beingsufiiciently' high to prevent theoperation of relays 202 and 203 butbeing sufficiently low such that' when'once operated, these rela'ysfwillremain operateddespite a subsequent disconnection of contacts 194 and195.

If after the governed speed of switches 191 and 192 has been reached,the accelerator pedal is maintained in a depressed position beyond thegoverned speed of 7 switch 212, said switch will operate therebyoperating lockup relay 203 and solenoid 208 while the ratio solenoid 205is still disengaged. 'The latter will then be operated upon a subsequentrelease of accelerator pedal 241. L V g I I If increasedaccelerationisdesired above .a governed speed of switch 212,downshifting switch 188 may be speed .of switches 191 and 19 2, vthelockup and f tive theelectrical control circuit for the selector 'valve48;

The manual controls "are operated as followsz 7 When hand lever 215 isin its downward and central position,tube 219 is lowered,therebyoperating starter control switch'186 to complete the circuittherethrouglr, and rotating both bell cranks 232 and 233 in aclockwisedirection'as viewed in Fig. 6, bell crank 232 being so moved bymeans'of a spring 238. This causes valve 63 to be conditioned to preventthe operation of brake 104, and to dump all fluid pressure in'the'system including that in the hydraulic torque converter 12. By dumpingall fluid pressure in this manner a considerable'load is removed fromthe starter as it turns the engine over.

When lever 215 is moved upward 'to the position wherein it can be movedeither to the reverse or forward position, bell cranks 232 and 233 arerotated in a counter-clockwise direction, crank 233 being so moved by aspring 239, tl1ereby rotating valve '63 to the position wherein pressuremay be built upto fill the torque converter'housing 22. 'The pressurethen releases: clutch 17 and conditions the torqueiconverter foroperation.

During the greater portion-of the time that lever. 215 is movingvertically, lug 228 is'riding in notch 227 in fixed bracket 226,andlever 215, therefore, cannot be rotated in either directioni At themp1 ofits travel, how ever,-lu'g1228 leaves notch 22'] and enters notch224 of pivoted lever 223. Hand control lever 215 may, therefore,'bemoved either to 1iever se or to forward position. When-moved toreverse ,position, switch 187 is disconneeted sothat the electricalcircuit is no longer opfe'ra I tive toetlect automatic shifts in thetransmission. Simultaneously, lever 139 is pulled to the left (Fig-6) torock shaft and engages reverse pawl 44. If the lever 215 ism s9 t e inwrd P o wi c 1 1 m t 13 render the electrical controls operative andlever 139 is pushed to the right (Fig. 6) to rock shaft 130 to disengagereverse pawl 44 and to engage forward pawl 40. During the lateralmovement of lever 215, valve 63 remains in its open position.

Carburetor control One of the principal difficulties encountered in theoperation of a transmission employing a hydraulic torque converter isthat of shifting into forward or reverse immediately after starting theengine on a cold day. Modern engines are almost universally equippedwith an automatic valve on the carburetor which automatically enrichesthe mixture to provide a fast idling speed in order that the engine maycontinue to operate and warm up in the shortest possible time. Since thetorque transmitted by the hydrodynamic torque converter is a function ofthe speed of rotation of the pump element thereof, a fast idling engineincreases the difiiculty with which positively interengageable forwardand reverse mechanisms such as pawls 40 and 44 may be operated. Toremedy this situation a control for valve 236 is employed. Bell crank232 and rod 235 are so arranged with respect to valve 236 that whenlever 215 is in its downward position corresponding to the position atwhich the starter may be operated, valve 236 is in the usual fast idlingposition so as to assist in warming up the engine. When lever 215 israised, however, prior to a shift into either forward or reverse such aswould entail the engagement of positively interengageable elements, bellcrank 232 is rotated in a manner to close valve 236 to the normal idlingposition. in this manner, the engine may be warmed up with a fast idlingcarburetor, but when the operator is ready to engage either the forwardor reverse driving mechanism, the idling speed is automatically droppedto that most favorable for the operation desired. The fast idle,therefore, is controlled by the operator and not by a thermostat as isusually the case and can be brought down to a normal value just prior toshifting into forward or reverse.

Summary of operations The operation of the transmission has beendescribed generally in connection with the detailed description of thetransmission, and the operation of each of the component features of thetransmission has been described along with the description of eachfeature. No detailed description of the operation of the transmission,therefore, is believed to be necessary herein. The operation, however,may be summarized as follows:

The principal control is the hand lever 215. While lever 215 is in itsneutral downward position, the engine may be started by closing starterswitch 135', switch 186 being closed at this position of lever 215.Valve 236 is in its fast idle position and when the engine commences torotate under its own power, drive shaft 1% and housing 22 will likewisebe rotated. Valve 63, however, is in its pressure dumping position,thereby preventing the building up of pressure within housing 22. Clutch17 will be engaged but since the remaining clutches and brakes aredisengaged, no power will be transmitted to driven shaft 14. If theoperator wishes to back the car, he raises lever 215 to its topposition, thereby engaging lug 228 with notch 225 in lever 223, and thenrotates lever 215 to the reverse position, thereby operating switch 187to disconnect the electrical controls and also moving reverse pawl 44into engagement. with its ratchet wheel 43. During the upward movementof lever 215, valve 236 is moved to a normal idling position and valve63 is rotated through the position wherein fluid under pressure isadmitted to housing 22, and then to the position wherein fluid underpressure is admitted to the hydraulically operated brake 104. Thisbrake, accordingly, is perated to arrest the rotation of reverse ratchetwheel 43 to enable pawl 44 to engage the wheel substantially 14 withoutclash. Any butt'endmg condition which may have existed at the timebecause of the blocker associated with the wheel was removed by thesubsequent release of brake 104 which permitted the wheel to rotate theblocker out of the way.

When the operator wishes to move forward, lever 215 is moved to theforward position thereby closing switch 187, disengaging reverse pawl 44and engaging forward pawl 49. Neither valve 63 nor valve 236 wasdisturbed during this maneuver. While lever 215 is in the raisedposition, however, it is impossible to operate the starter since switch186 is open by the upward movement of tube 219. If, after thetransmission is set for forward drive, the accelerator pedal isdepressed to start the car moving, pressure differential device 196breaks the circuit to solenoid 56 and thereby prevents the operation ofclutches 17 and 18. At a speed of approximately twelve miles per hour,speed controlled switches 191 and 192 will operate to complete thecircuit therethrough and render possible the engagement of clutches 17and 18. The engagement will occur when accelerator pedal 241 is releasedso as to create vacuum in pressure differential device 196 and move itin a direction to operate switches 194 and 195. When these switches areoperated, solenoid 56 will move valve 48 to a position to admit fluidunder pressure into both conduits 49 and 47 to operate both clutches. Adownshift is made possible by operating downshifting switch 138. It iscontemplated that this switch shall be operated by the accelerator pedalduring a movement of the latter past its wide open position. Thebreaking of the circuit through contacts 189 and 199 causes solenoid 56to be deenergized, which in turn causes spring 178 to pull valve 48 toits pressure dumping position. Clutches 17 and 18, therefore, will bedisengaged. Above the governed speed of switch 212, however, a downshiftinto the torque converter is impossible and likewise, above the governedspeed of the switch 212, a

delay in the operation of clutch 17 by virtue of the open condition ofswitch 193 is also impossible.

serve to drive a vehicle under all of the normal conditions which mayexist, and that the drive will be ex-- tremely eflicient' despite thefact that a hydraulic torque converter constitutes an important part ofthe transmission. remedied by suitable controls to render unnecessaryany special instructions to an operator by virtue of the presence of theconverter. All rotating parts have been made extremely light to reducerotational inertia to compensate for the increase in rotational inertiawhich results from the mass of fluid and associated parts present in theconverter. A combination of hydraulic and electrical controls is usedwhich provides for the automatic operation of the transmission with aminimum of complexity. Thus, the hydraulic system per se is quitesimple, and the electrical system, likewise, is quite simple.

It is understood that the foregoing description ismerely illustrative ofa preferred embodiment of the invention and that the scope of theinvention, therefore, is not to be limited thereto but is to bedetermined by the appended claims.

We claim:

1. A transmission comprising driving and driven shafts, a hydrodynamicdevice driven from the drive matically releasable means for holding thesupporting;

means against reverse rotation, and an automatically releasableconnection between the stator and'the common.

The various defects of the converter-have beenrelative to said support.

' '2. A transmission comprisingdr-iving and drivensha'fts,

' a hydrodynamic device driven from, the drive shaft, dif

ferenti-al gearing connected to drive the driven shaft,

said gearing comprising a sun'gear adapted'to act as a fulcrum fortorque multiplication, planet pinions, a carrier for the planet pinionsand a ring gear directly conreleasable brakeforthe sun gear, said brakebeing effective automatically to'release the gearing when the' carrieris connected to the ring gear. 1 i

3. A transmission comprising driving and driven shafts,

, a hydrodynamic device driven from the drive shaft, said devicecomprising a pump element,'a turbine element and a stator element;difierential gearing connected to drive the driven shaft and comprisinga sun gear adapted to act as a fulcrum for torque, multiplication,planet pinions, a carrier for the planet pinions, and a ring geardirectly connected to the driven shaft; means directlyconnecting theturbine element and carrier, common supporting means for the sun gearand stator, a releasable connection between the stator and supportingmeans, a manually controlled brake for the sun gear, a manuallycontrolled brake for the carrier, the sun gear brake when appliedproviding a reaction point for the stator and sun gear for forward driveand the carrier brake when applied serving to interchange the functionsof the turbine and stator elements to provide a reverse drive throughthe gearing, means for directly connecting the ring gear and carrier fordirect drive and means for automatically breaking the connection betweenthe sun ge'ar'and the sun gear brake when said direct drive iseffective.

4. A transmission comprising driving and driven shafts,

a hydrodynamic device driven fiom the drive shaft, difierential gearingconnected to drive the driven shaft, and means for transmitting thedrive from the hydrodynamic devicerto the gearing, said gearingincluding a cast metal bine' element, and meansfor providing a fulcrumfor torque multiplication; a clutch for providing a direct connectionbetween the turbine element and drive shaft, said clutch comprisingadriven element rotatable 'with the turbine element and apressuredifierential device, said last-mentioned device, being. exposedto the fluid under pressure in the housing'at all times,' res ilientmeans constantly biasing the clutch to engaged position, said resilientmeans supplying insufiicient'for'ce to maintain the clutch engaged whenthe housing is substantially filled with fluid under pressure, and means'for supplying fluid under greater pressure to the pressure differentialdevice for overcoming the pressure'of' the fluid withinthe housing andthereby engaging the clutch. '8. A transmission comprising driving anddriven shafts, a hydrodynamic device driven from the drive shaft, saidhydrodynamic device including a'housing substantially filled with fluidunder pressure, differential gearing connect ed to drive'the drivenshaft, means for transmitting the drive from the hydrodynamic device tothe gearing, means for locking up the hydrodynamic device for oneto-onedrive therethrough, means for providing a direct drivethrough thegearing, power means for operating the lockup means and the direct drivemeans, means for normally breaking the drive between the driven anddrive shafts'when the driven shaft becomes the driver, additional meansconstantly tending to engage the lockup means, and manually operablemeans cooperating with the gearing to provide a substitute drive betweenthe driven and drive shafts through the gearing and lockup means, saidsubstitute drive being independent of the power means for operating thelockup and direct drive. means. i

9. A transmission comprising driving and driven shafts, a hydrodynamicdevice driven from the drive shaft, differential gearing connected todrive the driven shaft,

7 means transmitting the drive from the hydrodynamic ring gear, alight-weight sheet metal drum connecting the ring gear to the drivenshaft, and means within the drum for directly connecting the drivenshaft to thefhydro-. dynamic device, thereby to by-pass the gearing. a ri a 5. A transmission comprising driving and driven shafts, ahydrodynamic device driven from the'drive shaft; differential gearingconnected to drive the driven" shaft, and means for transmitting thedrive' from the hydrodynamic device to the gearing, said gearingincluding a ring gear, a a light-weight sheet 'metal drum connecting thering gear to the driven shaft, said drum having an annular recess formedtherein and constituting anta'nnular cylinder, means within the drurnfor directly connecting the driven shaft to the hydrodynamic device, andpiston means in the cylinder for operating the direct connecting meansthereby to by-pa ss the gearing. 1

device to the gearing manually operated positive devices for producingselectively a reverse drive or a reduced drive through the transmission,power-operated means for producing a one-to-oneldrive through thehydrodynamic device, power-operated means for producing a direct drivethrough, the gearing, and additional means for producing a reduced drivethrough thetgearing only when the driven shaft is the driver, saidlockup means for the hydrodynamic device being normally operative tolock up the device and to' providea direct connection between the driveshaft and the gearing.

10. A transmission comprising driving and driven shafts, a hydrodynamicdevice driven from the drive shaft, differential gearing connected todrivethe driven shaft, means transmitting the drive'from the hydrody- 6.A transmission comprising driving and driven shafts,

a hydrodynamic device driven from the drive shaft, differential gearingconnected to drive the driven shaft, means transmitting the drive fromthe hydrodynamic device to the gearing, toothed devices associated withthe gearing and manually operable to establish forward, reverse andneutral' conditions in the transmission, power-operated means forby-passing the hydrodynamic device and gearing device comprising ahousing, fluid under pressure in the housing,apump element driven fromthe housing, a tinnamic device to the gearing, tmeansfor establishing aone-to-one drive through the hydrodynamic device, means forestablishinga direct drive through the gearing, said one-to-one drivemeans and direct drive means being power-operated, and means responsiveto the speed of rotation of one of said shafts for controlling theoperation of the power-operated means. 1

11. A transmission device asdcscribed in claim 10, an engine connectedto the drive shaft, said engine being adapted to create a vacuum inaccordance with the condition of operation thereof, and means controlledby the vacuum so produced for delaying the operation of thepower-operated means. a

' 12. A transmission comprising driving and driven shafts, a hydraulictorque converter driven from .the drive shaft, planetary gearingconnected to drive the driven shaft, means transmittingthe drive fromthehydraulic torque converter to the gearing, means for locking up thetorque converter, means for locking up the gearing to provide a directdrive therethrough, means responsive to the speed of rotation of one ofthe shafts for controlling the lockup means for the torque converter andgearing, means for delaying the operation of said lockup means snaresafter it is conditioned for operation by the speed responsive means, andadditional speed responsive means operable as a function of the speed ofrotation of one of said shafts to lock up the torque converter above apredetermined speed of rotation of said speed responsive meansregardless of the condition of operation of the delaying means.

13. A transmission comprising driving and driven shafts, a hydraulictorque converter driven from the drive shaft, differential gearingconnected to drive the driven shaft, means transmitting the drive fromthe torque converter to the gearing, means for locking up the torqueconverter, means for producing a direct drive through the gearing, meansresponsive to the speed of rotation of one of the shafts forsimultaneously operating the lockup means for the torque converter andthe gearing, and means under the control of the operator forsimultaneously rendering inoperative the means for locking up the torqueconverter and gearing after the lockup means has been operated.

14. A transmission device as described in claim 13, and additional meansfor rendering the manually con trolled means ineffective to unlock thetorque converter.

15. A transmission comprising driving and driven shafts, a torqueconverting device driven from the drive shaft, a second torqueconverting device connected to drive the driven shaft, means fortransmitting the drive from the first torque converting device to thesecond, means for providing a one-to-one drive through the first device,means for providing a one-to-one drive through the second device, fluidmeans for operating each of said devices, a pair of valves forcontrolling the fluid means, electromagnetic means for controlling thevalves, and switch means responsive to the speed of rotation of one ofthe shafts for simultaneously operating both valves to provide a directdrive between the driving and driven shafts.

16. A transmission device as described in claim 15, an engine connectedto the drive shaft, said engine being adapted to operate under varyingconditions in response to operator control thereof, and switch meansresponsive to the various conditions of operation of the engine fordelaying the operation of the valves until the engine is conditioned forsubstantially idling operation.

17. A transmission device as described in claim 15, means for delayingthe operation of the valves after they have been conditioned foroperation by the speed responsive switch means, and additional speedresponsive means, operable as a function of the rotation of one of theshafts, for rendering the delay means ineffective as to the valvecontrolling one of the one-to-one drive means for the torque converter.

1 8. A transmission device as described in claim 15, and manuallycontrolled switch means for rendering the speed responsive switch meansineffectual to cause the operation of either valve.

19. A transmission device as described in claim 15, means forsimultaneously rendering the speed responsive control means ineffectualto operate both valves, and means effective as a function of the speedof rotation of one of the shafts for limiting the effectiveness of thelastmentioned means to but one of the valves.

20. A transmission comprising driving and driven shafts, a hydraulictorque converter driven from the drive shaft, differential gearingconnected to drive the driven shaft, means transmitting the drive fromthe converter to the gearing, means for locking up the converter, meansfor providing a direct drive through the gearing, fluid means foroperating the lockup and direct drive means, a pair of valvescontrolling the fluid means, electromagnetic means controlling thevalves, a switch responsive to the speed of one of the shafts forcontrolling the valves whereby to condition them for operation above apredetermined speed of rotation of said shaft, manually controlled meansfor overcontrolling the speed responsive means to disconnect the lockupin the converter and the direct drive in the gearing, and speedresponsive means effective above a predetermined speed of rotation ofone of said shafts for limiting the effectiveness of the lastmentionedmeans to the valve controlling the direct drive through the gearingwhereby the converter remains locked up above said predetermined speedof rotation regardless of the operation of said manual overcontrolmeans.

21. A transmission comprising in combination, driving and driven shafts,a hydrodynamic device, said device including impeller element, a rotorelement and a stator element, said impeller element being connected withsaid driving shaft to be driven thereby, said stator element whenrestrained in rotation being adapted to cause the rotor element to bedriven at multiplied torque, differential gearing connected to drivesaid driven shaft, means transmitting the drive from said rotor elementto said gearing, means for Dy-passing the hydrodynamic device andgearing to provide a direct drive between said shafts, and a commonreleasable reaction means for the gearing and said stator elementfunctioning to restrain the stator element from rotation, said reactionmeans being automatically released when said hydrodynamic device andsaid gearing are by-passed.

22. A transmission comprising driving and driven shafts, a hydrodynamicdevice driven from the drive shaft and including a stator element formultiplying torque, differential gearing connected to drive the drivenshaft, means transmitting the drive from the hydrodynamic device to thegearing, means for by-passing the hydro-- dynamic device and gearing toprovide a direct drive between the shafts, a common releasable reactionmeans for the gearing and the stator element of the hydrodynamic devicewhich is automatically released when the gearing is by-passed, andmanual control means for the releasable reaction means whereby saidreaction. means may be released at the option of the operator. I

23. A transmission comprising in combination, driving and driven shafts,a hydrodynamic device, saidldevice in cluding an impeller element, arotor element and a stator element, said impeller element beingconnected with said driving shaft to be driven thereby, said statorelement when restrained in rotation being adapted to cause the rotorelement to be driven at multiplied torque, differential gearingconnected to drive the driven shaft, means transmitting the drive fromsaid rotor element tos'a'id gearing, tmeans for by-passing thehydrodynamic device andgearingto provide a direct drive between saidshafts, and a. one-way brake common tothe gearing and to said statorelement for providing a releasable reaction means therefor andrestraining the rotation of the stator element, said one-way brake beingautomatically released when said hydrodynamic device and said gearingare by-passed;

24. (In a control mechanism for a power transmitting device, said deviceincluding a driving shaft, a driven shaft, a rotatable elementandanother element engageable therewith, said elements cooperating tocomplete a power train through said device between said shafts, anoperator for effecting the engagement of the elements, means biasing theoperator to effect the engagement, means adapted to be acted upon byopposed differential pressures and associated with the operator andnormally effective as a function of the operation of the powertransmitting device to counteract the biasing means and therebydisengage the elements, and means operative at a predetermined speed ofrotation of one of said shafts for causing said second-named means toassist the biasing means to effect an engagement of the elements.

25. In a control mechanism for a power transmitting device, said deviceincluding a driving shaft, a driven shaft, a rotatable element andanother element engageable therewith, said elements cooperating tocomplete a power train through said device between said shafts, anoperator for effecting the engagement of theelements, a springconstantly biasing the operator to efiect the en- 19 gagement, meansadapted to be acted upon by opposed differential pressures andassociated with the operator and normally effective as a function of theoperation of the power transmitting device to counteract the spring andthereby disengage the elements, and means operative at a predeterminedspeed of rotation of one of said shafts for causing said first-namedmeans to assist the spring to effect an engagement, of the elements.

26; In a control mechanism for a power transmitting device, said deviceincluding a driving shaft, a driven shaft, a rotatable element andanother element engageable therewith, said elements cooperating tocomplete a power train through said device between said shafts, anoperator for effecting the engagement ,of the elements, means biasingthe operator to effect the engagement, a pistonassociated with theoperator and normally effective as a function of the operation of thepower transmitting deviceto counteract'the biasing means and therebydisengage the elements,.and means operative at a predetermined speed ofrotation of one of said shafts for introducingfluid under'pressurebehind the piston to cause t-he'piston to assist the biasing means toeffect an engagement of the elements.

' tive as a function of. the operation of the power transmitting deviceto maintain the elements disengaged, spring means continuously effectiveupon the operator to bias the elements to engaged position, and meansoperative ata predetermined speed of rotation of one' of said shafts forcausing the'piston to assist the spring means to effect an engagement.of the elements.

28. "A combination as described in claim 27, the op erator and pistoncomprising a single unit which is movable as a whole to control theelements.

29. In combination, a driving shaft, a driven shaft, ahydrodynamic powertransmitting device having a driving or, impeller element and a drivenor rotor element,

said driving element being adapted to be 'driven by said driving-shaftand said driven element being adapted to drive said driven shaft, ahousing for the device, a clutch,

within the housing and adapted to connect the driving and drivenelements together and thereby to complete a power train between saidsha-fts, fluid in the housing, said fluid being placed under pressure'asa function of the rotation of'the driving element; an operator for theclutch,

, means adapted to be acted upon by opposed differential pressures andassociated with the operator and sensitive to the fluid pressure'in thehousing for biasing said means to disengage the clutch, means efiectivebelow a predetermined pressure in the housing for effecting theengagernent of the clutch, and means operative at a predetermined speedof rotation of said driven shaft for overcoming the fluid pressure inthe housing to efiect engagement of the clutch. V 7 30. in combination,adriving shaft, a driven shaft, a hydrodynamic power transmitting devicehaving a driving or impeller element and a driven or rotor element,

said driving element being adapted to be driven by said dIlVlIlg shaftand said driven element being adapted to ing the piston in an oppositedirection to effect the en gagement of the clutch, said last-named meansexerting less pressure on the piston than the fluid under pressure insaid housing, and other meansadapted to befeifective above apredetermined speed of rotation of said driven shaft for overcoming thefluid pressure in said housing to effect engagement ofsaid clutch. v

31. In combination, a hydraulic torque converter comprising a pumpelement, a driven or turbine element, and a stator element, a housingfor the converter, a clutch within the housing and adapted to connectthe pump and turbine elements together, fluid in the housing, a pump forplacingtlie fluid in the housing under preSsure said pump being drivenwith the converter pump element, a pressure member for the clutch, apiston associated with the pressure member and on one sidethereof beingexposed to thefluid pressurein the housing for biasing the pressuremember to disengage the clutch, spring means constantly biasing thepressure member to engage the clutch, said spring means being lesspowerful than the total pressure developed by the fluid in the housingacting upon the piston, and means for applying fluid under pressure uponthe opposite'side of the piston to overcome the pressure of fluid in thehousing on the piston to engage the clutch regardless of the pressurewithin the housing. T r v 7 32. A transmission for an automotive vehiclecomprising driving and driven shafts, a hydraulic torque converterdrivenfrom said drive shaft, planetary gearing connected to drive said drivenshaft, means transmitting the drive from said torque converter to saidgearing, a clutch for locking up said torque converter, a clutch forlocking up said gearing to provide a direct drive therethrough, powermeans for operating :both of said clutches, means responsive to thespeed of rotation of one of said shafts for controlling said power meansto cause engagement of said clutches as the 'the speed of said one shaftincreases, an accelerator for the vehicle, and means'respo-nsive tomovement of said accelerator past the open throttle posi: tion for,overruling said speed responsive means and dis engaging both of saidclutches whereby the drive is transmitted through said torque.converter'and said gearing.

33; A transmission for an automotive vehicle comprising driving anddriven shafts,'a hydraulic torque converter driven from said driveshaft,';p1anetary gearing connected to drive said driven shaft, meanstransmitting the drive from said torque'converter to said gearing, aclutchfor locking up said torque converter, a clutch for locking up saidgearing to provide a direct drive therethrough, power means foroperating both of said clutches, means responsive to the speed of thevehiclefoncontrolling the operation of said power means to causeengagement of both of said clutches as the speed of the vehicleincreases, an accelerator for the vehicle, and means responsive tomovement of said accelerator past the open throttle position foroverruling said speed respondrive saiddriven shaft, a housing for the,device, a clutch within the housing and adapted to connect the drivingand driven elements together and thereby complete a power train betweensaid shafts, fluid in the housing,- a

pump driven with said driving element for placing the fluid in thehousing under pressure, 'an operator for the clutch, a piston associatedwiththe operator and having one side exposed to the fluid in the housingwhereby to cause the operator-to disengage the. clutch, means biassivemeans below a predetermined vehicle speed and disengaging both of saidclutches whereby the drive is transmitted through said torque converterand said gearing, said accelerator responsive means being ineffective tooverrule said speed responsive means with respect to one of saidclutches above said predetermined vehicle speed so that said last-namedclutch remains engaged when said accelerator is moved to its openthrottle position.

' 34. A transmission comprising driving and driven shafts, a hydraulictorque converter driven from said drive shaft, planetary gearingconnected to drive said driven shaft, means transmitting the drive' fromsaid torque converter to said gearing, a clutch for locking'up saidtorque converter, a. clutch for locking up said gearing to provide adirect drive therethrough, power means foroperating both'of saidclutches, and means responsive to the speed of rotation of said drivenshaft for controlling the operation of said power means so as. to causeengagement of said clutches when said driven shaft reaches a 21predetermined speed, said speed responsive means disengaging both clutchmeans on a decrease in speed whereby the drive is transmitted throughsaid gearing and torque converter.

35. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydrodynamic coupling device drivenfrom said drive shaft, gearing for completing a drive from saidhydrodynamic device to said driven shaft, means providing a direct drivebetween said shafts by-passing said hydrodynamic device and including afluid pressure engaged friction clutch for completing the drive, a speedresponsive governor, mechanism variable with changes in torque demand bythe vehicle operator and means for applying fluid pressure to saidclutch to engage it under the joint control of said governor and saidtorque demand variable mechanism.

36. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydraulic torque converter drivenfrom said drive shaft, gearing for completing a drive from saidhydraulic torque converter to said driven shaft, means providing adirect drive between said shafts by-passing said hydraulic torqueconverter and including a fluid pressure engaged friction clutch forcompleting the drive, a governor responsive to the speed of said drivenshaft, mechanism variable with changes in torque demand by the vehicleoperator, at source of fluid pressure, and valve mechanism under thejoint control of said governor and said torque demand variable mechanismto connect said pressure source with said clutch to engage the clutchwhen the speed of said driven shaft increases and the torque demanddecreases.

37. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, an intermediate shaft, a hydrodynamiccoupling device driven from said drive shaft and driving saidintermediate shaft, gearing between said intermediate and driven shaftsfor completing a drive between said drive and driven shafts through saidhydrodynamic device and the gearing, a clutch for directly connectingsaid drive and intermediate shafts to by-pass said hydrodynamic device,a speed responsive governor means, mechanism variable with changes intorque demand by the vehicle operator, and means for engaging saidclutchunder the joint control of said governor means and said torquedemand variable mechanism.

38. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, an intermediate shaft, a hydraulictorque converter driven from said drive shaft and driving saidintermediate shaft, gearing between said intermediate and driven shaftsfor completing a drive through said torque converter and the gearingbetween said drive and driven shafts, a fluid pressure engaged frictionclutch for connecting said drive and intermediate shafts for by-passingsaid torque conver-ter, a source of fluid pressure, a governorresponsive to the speed of said driven shaft, mechanism variable withchanges in torque demand by the vehicle operator, and means under thejoint control of said governor and said torque demand mechanism forconnecting said pressure source and said clutch to engage the clutchwhen the speed of said driven shaft increases and the torque demanddecreases.

39. in transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydrodynamic coupling device drivenfrom said drive shaft, gearing for completing a drive from saidhydrodynamic device to said driven shaft, means providing a direct drivebetween said shafts lay-passing said hydrodynamic device and including afluid pressure engaged friction clutch for completing the drive, a speedresponsive governor means, means variable with changes in torque demandby the vehicle operator, means for applying fluid pressure to saidclutch to engage it under the jointxcontrol .of said governor means andsaid torque 22 demand variable means When the speed is increased and thetorque demand is decreased, and means for disapplying fluid pressure tosaid clutch to disengage said clutch when said torque demand variablemechanism is moved past open position and the torque demand isincreased.

40. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydraulic torque converter drivenfrom said drive shaft, gearing for completing a drive from said torqueconverter to said driven shaft, means providing a direct drive betweensaid shafts by-passing said torque converter and including a fluidpressure engaged friction clutch for completing the drive, a source offluid pressure, governor means responsive to the speed of said drivenshaft, mechanism variable with changes in torque demand by the vehicleoperator, valve mechanism under the joint control of said governor meansand said torque demand variable mechanism for connecting said pressuresource with said clutch for engaging the clutch When the speed of saiddriven shaft increases and the torque demand is decreased, anaccelerator for the vehicle, and means under the control of saidaccelerator and effective on said valve mechanism for disconnecting saidpressure source and said clutch to cause disengagement of the clutchwhen the accelerator is moved in an operative stroke past the openthrottle position.

41. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, an intermediate shaft, a hydraulictorque converter driven from said drive shaft and driving saidintermediate shaft, gearing driven from said intermediate shaft anddriving said driven shaft for completing a drive between said drive anddriven shafts through said torque converter and the gearing, a .1 idpressure engaged friction clutch for connecting said drive andintermediate shafts for bypassing the hydraulic torque converter, agovernor responsive to the speed of said driven shaft, mechanismvariable with changes in torque demand by the vehicle operator, a sourceof fluid pressure, and valve means under the joint control of saidgovernor and said torque demand variable mechanism for connecting saidpressure source and said clutch for engaging the clutch when the drivenshaft speed increases and the torque demand decreases, an acceleratorfor the vehicle, and means under the control of said accelerator andeffective on said valve means to block said clutch With respect to saidpressure source and cause disengagement of said clutch when theaccelerator is moved in an operative stroke past the open throttleposition. 1 42. 'In transmission mechanism for an automotive vehicle,the combination of a drive shaft, a driven shaft, a hydrodynamiccoupling device driven from said drive shaft, planetary gearing forcompleting a first speed drive from said hydrodynamic device to saiddriven shaft, a clutch for locking together two elements of said gearingfor providing a second speed drive between said shafts through saidhydrodynamic coupling device, means for providing a direct drive betweensaid shafts by-passing said hydrodynamic device and including a secondclutch for completing the drive, a speed responsive governor, mechanismvariable with changes in torque demand by the vehicle operator, andmeans for engaging each of said clutches under the joint control of saidgovernor and said torque demand variable mechanism.

43. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydraulic torque converter drivenfrom said drive shaft, planetary gearing for completing a low speeddrive from said hydraulic torque converter to said driven shaft, a firstfluid pressure engaged friction clutch for locking together two elementsof said gearing so as to provide an intermediate speed drive betweensaid shafts through said torque converter, means providing adirectfdn've between said shafts by-passing said torque converter andincluding a second fluid pressure engaged friction clutch e determinedspeedofthe vehicle,

for completing the drive, a source of fluid pressure, a gov.- ernorvdrivenby said driven shaft, mechanism variable with-changes in torque,demand by the vehicle operator, and valve means under the joint controlof said governor and said torque demand mechanism for connecting saidpressure source with each of said clutches as the'speed of said drivenshaft increases and said torque demand decreases.

44. In transmission mechanism for an automotive,

.vehicle,-the combination of a drive shaft, a driven shaft, a hydraulictorque converter driven from said drive shaft, planetary gearing forcompleting a low speed drive between said shafts through said torqueconverter, 7 a first friction clutch for locking together two elementsof said gearing for providing'an intermediate speed drive between saidshaftsrthrough said converter, means pro-' viding a direct drive betweensaid shafts by-passin-g said torque converter and including'a secondfriction clutch.

for completing the drive, a governor driven by said driven shaft,-mechanism variable With changes in torque demand said governor and saidtorque demand mechanism for engaging eachor" said clutches when thedriven shaft speed increases and the torque demand decreases, 'anaccelerator for the vehicle, and means under the control 7 of saidaccelerator for disengaging said clutches when the drive and drivenshafts including said torque converter,

a first fluid pressure engaged friction clutch for connecting togethertwo elements of said gearing to provide an intermediate speed drivebetween said shafts through said torque converter, means providing adirect drive between said drive and driven shafts by-passing said torqueconverter including a second fluid pressure engaged friction clutchfor'connecting said drive and intermediate shafts and completing thedirect drive when engagedvvith said first clutch, a governorj responsiveto the speed of said driven shaft, mechanism variable with changes intorque demand by the vehicle operator, a source of fluid pressure, meansunder the joint control of said governor and said torque demandmechanism for connecting said pres sure source with each of saidclutches for engaging each 46.Inftra nsmission mechanism for anautomotive 'vehicle, the combination of a drive shaft, a driven shaft,

a hydraulic torque converter driven from said drive shaft,

. planetary gearing for completing a first speed drive between saidshafts including said torque converter, a clutch for locking togethertwo elements of said gearing to provide a second speed drive betweensaid shafts including said hydraulic torque converter, means forproviding a' direct drive between said shafts by-passing said torqueconverter and including a second clutch for completing the drive, andmeans for: controlling engagementof said clutches and including meansresponsive to the speed of the vehicle-effective with respect to one ofthe clutches at a predetermined low speedrof the vehicle and efiectivewith respect tothe other of said clutches ata higher pre- '47.' Intransmission 'mechanism for an automotive 7 vehicle, the combination ofa drive shaft, a driven shaft,

n hydraulic torque converter driven fromsaid'drive shaft,

1 planetary gearing for completing a first speed drive be.- tweensaidshafts including said torque converter, a clutch for locking togethertwo elements -of said gearing to provide a second speed drive betweensaid shafts including .said hydraulic torque converter, a fluid pressureengaged friction clutchv for locking together two elements of saidgearing to provide a second speed drive between said shafts includingsaid hydraulic torque converter, means for providing a direct drivebetween said shafts by-passing .saidtorque converter and including asecond fluid pressure engaged friction clutch for completing the drive,a source .of fluid pressure, valve means for connecting said pressuresource and said clutches, andmeans for controlling said valve means andincluding means responsive to the speed of the vehicleeifective tocontrol the valve means with respect to one of said clutches at acertain predetermined low speed of the vehicle and effective to controlthe valve means with respect to the other of said clutches at higherpredetermined speed of the vehicle. 7 j 48. In transmission mechanismfor an automotive vehicle, the combination of a drive shaft, a drivenshaft,

by the vehicle operator, means under the joint control of v anaccelerator'for the vehicle, a hydraulic torque converter driven fromsaid drive shaft, planetary gearing for completing a first speed drivebetween said shafts including said torque converter, a clutch forlocking together two elements'ofsaid gearing to provide a second speeddrive between said shafts including said hydraulic torque converter,means for providing .a direct drive between said shafts by-passing saidtorqueconverter and including a second clutch for completingthe drive,means for controlling engagement of said clutches and including meansresponsive to the speed of the vehicle effective with respect to one ofthe clutches at a predetermined low speed of the vehicle'and effectivewith respect .to the other of said clutches a higher predetermined.speed of the vehicle, and means under the control of said acceleratorfor causing disengagement of one of said clutches when the acceleratoris moved in an operative stroke past the open throttle position. v 1

' .49. In transmission. mechanism for an automotive vehicle,the'combination ofia drive shaft, a driven shaft, mechanism'variable.with changes in torque demand by the vehicleoperator, a hydraulictorque converter-driven from said drive shaft, planetary-gearing forcompleting a first speed drive between said shafts including said torqueconverter, a clutch for locking together twoelements of said gearing toprovide a second speed drive between said shafts including saidhydraulic torque converter, means for'providing a direct drive betweensaid shafts 'by-passi-ng said,-,torque converter. and including a secondclutch for completing the drive, means for controlling engagement ofsaid clutches and 'including'means responsive to the speed ofthevehicleeffective with respect to one of the clutches at apredetermined: low speed .of the vehicle and effective .with respect tothe other of said clutches a higher predetermined speed of the vehicle,and means responsive to said torque demand variable mechanism formodifying the action of said speed responsive means with respect to oneof said clutches to cause engagement of the the vehicle operator, meansunder the, control of said torque demand mechanism for engaging saidclutch'when the .torque demand is decreased, and means under the.

control of said governor for rendering said torque demand mechanismsoeffective above a predetermined vehicle speed, and inefiective belowsaid predetermined'vehicle 25 speed and causing engagement of saidclutch regardless of torque demand at a predetermined higher vehiclespeed.

51. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydraulic torque converter drivenfrom said drive shaft, gearing for completing a drive fromsaid hydraulictorque converter to said driven shaft, means providing a direct drivebetween said shafts by-passing said torque converter and including afriction clutch for completing the dri e, mechanism responsive to thespeed of the vehicle, means responsive to the torque demand by thevehicle operator, means for engaging said clutch under the joint controlof said speed responsive mechanism and said torque demand mechanism whenthe vehicle is travelling above a predetermined speed and the torquedemand decreases, an accelerator for the vehicle, and means under thecontrol of said accelerator on an operative stroke thereof past the openthrottle position for disengaging said clutch, said speed responsivemechanism being operative above a higher predetermined speed of thevehicle for engaging said clutch regardless of movement of theaccelerator past its said open throttle position.

52. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydraulic torque converter drivenfrom said drive shaft, planetary gearing for completing a first drivebetween said shafts including said torque converter, a clutch forlocking together two elements of said gearing for providing a seconddrive between said shafts through said torque converter, means forproviding a direct drive between said shafts by-passing said torqueconverter and including a second clutch for completing the drive, meansresponsive to the speed of the vehicle, mechanism variable with changesin torque demand by the vehicle operator, means for engaging each ofsaid clutches under the control of said torque demand variable mechanismwhen the torque demand is decreased, and means under the control of saidspeed responsive mechanism for preventing such clutch engagement below apredetermined vehicle speed and overruling the torque demand mechanismwith respect to said direct drive clutch to engage the clutch above ahigher predetermined vehicle speed.

53. In transmission mechanism for an automotive vehicle, the combinationof a drive shaft, a driven shaft, a hydraulic torque converter drivenfrom said drive shaft, a planetary gearing for completing a first drivefrom said torque converter to said driven shaft and including a one- Waybrake mechanism for taking the reaction of the gearing to complete thedrive, a clutch for locking together two elements of said gearing forproviding a second drive between said shafts through said torqueconverter, means for providing a direct drive between said shaftsby-passing said torque converter and including a second clutch forcompleting the drive, a speed responsive governor, and means forengaging each of said clutches under the control of said governor.

54. A transmission comprising driving and driven shafts, a hydraulictorque converter driven from said drive shaft, planetary gearing havinga plurality of elements and connected to drive said driven shaft fromsaid torque converter, means including a one-way brake for braking oneof the elements of said gearing for completing the drive between saidtorque converter and driven shaft, a friction clutch for lockingtogether two elements of said gearing so as to provide a direct drivebetween said torque converter and said driven shaft with said onewaybrake overrunning, means providing a direct drive etween said drivingand driven shafts by-passing said torque converter and including afriction clutch for completing the drive.

55. A transmission comprising a driving shaft, a driven shaft, anintermediate shaft, a hydraulic torque converter driven from said driveshaft and driving said intermediate shaft, planetary gearing driven fromsaid intermediate shaft and driving said driven shaft, braking mechanismincluding a one-way brake for braking an element of said gearing so asto complete a reduced speed drive between said driving and driven shaftsincluding said torque converter and said gearing, a friction clutch forconnecting together two elements of said gearing so as to lock up thegearing to provide a higher speed drive between said driving and drivenshafts with said one-way brake overrunning, and a second friction clutchfor directly connecting said driving and intermediate shafts so as toprovide a drive between said driving and driven shafts exclusive of saidtorque converter.

56. In transmission mechanism, the combination of a drive shaft, adriven shaft, means providing a power train between said shaftsincluding a hydraulic torque converter, said torque converter having aplurality of elements with blades adapted to co-act with a fluid andhaving a housing for the fluid, means for providing an alternate powertrain between said shafts exclusive of said torque converter andincluding a friction clutch in saidhousing, said clutch comprising aclutch applying piston exposed to fluid pressure in said housing, meansfor regulating fluid in said housing to a low pressure, and means forsupplying fluid under pressure behind said piston at a higher pressureso that the piston may move against the pressure within said housing toengage said clutch.

57. In transmission mechanism, the combination of a drive shaft, adriven shaft, means providing a power train between said shaftsincluding a hydraulic torque converter, said torque converter having aplurality of elements with blades adapted to co-act with a fluid andhaving a housing for the fluid, means for providing an alternate powertrain between said shafts exclusive of said torque converter andincluding a friction clutch in said housing, said clutch comprising aclutch applying piston exposed to fluid pressure in said housing, meansincluding a regulating valve for regulating the fluid in said housing toa predetermined low pressure, and means including a second regulatingvalve for supplying fluid under pressure behind said piston at a higherpressure so that the piston may move against the pressure within saidhousing to engage said clutch.

58. In transmission mechanism, the combination of a drive shaft, adriven shaft, means providing a power train between said shaftsincluding a hydraulic torque converter, said torque converter having aplurality of elements with blades adapted to co-act with a fluid andhaving a housing for the fluid, means for providing an alternate powertrain between said shafts exclusive of said torque converter andincluding a friction clutch in said housing, said clutch comprising aclutch applying piston exposed to fluid pressure in said housing, a pumpconnected to supply fluid to said housing and also be hind said pistonso that the piston may move to engage said clutch, a regulating valvefor maintaining the fluid supplied to said piston at a predeterminedhigh pressure, and a second regulating valve for regulating the fluidwithin said housing at a predetermined low pressure so that the pistonmay move against the pressure within said housing.

59. In transmission mechanism, the combination of a drive shaft, adriven shaft, means providing a power train between said shaftsincluding a hydraulic torque converter, said torque converter having aplurality of elements with blades adapted to co-act with a fluid andhaving a housing for the fluid, means for providing an alternate powertrain between said shafts exclusive of said converter and including afriction clutch in said housing, said clutch comprising a clutchapplying piston exposed to fluid pressure in said housing, a source offluid pressure including a pump connected with said housing to supplyfluid thereto, selector valve means for connecting said pressure sourcewith said piston so as to apply fluid pressure hehind said piston tomove the piston to engage said clutch, a first regulator valve forregulating the fluid supplied to said clutch at a predetermined highpressure,,and a second 'regulator valve for regulating the fluidsupplied to said housing to a predetermined low, pressure so that thepiston may move against the fluid pressure in said housing. a 7

' 60. In transmission mechanism, the combination of a drive shaft, adriven shaft, means providing a power train between said shaftsincluding "a hydraulic torque converter, said torque converter having aplurality of elenients with blades adapted to co-act with a fluid an'dhaving a housing for the fluid, means for providing an alternate powertrain between said shafts exclusive of said torque converter andincluding a friction clutch in said housing, said clutch comprising aclutch applying piston exposed to fluid pressure in said housing, asource of,

fluid pressure including a pump which is connected to supply fluid tosaid housing, selector valve means for selectively connecting said pumpwith said piston to, ap-

to engage said clutch, a regulator valve for regulating the I ply fluidpressure behind the piston to movethe piston a References Cited in thefile of this patent UNITED STATES PATENTS 1,967,730 Zadig July 24; 19342,105,429' Maybach Jan; 11, 1938 2,120,104 -Livermore L. Iune7, 19382,226,802 Black Dec. 31', 1940 2,'351,213 James Iune'13, 1944 2,380,677Schjolirl July 31, 1945 Schneider Dec; '14, 1948 W lav -fr

